Cylinder head construction



June 6, 1939; J. P. BURKE CYLINDER HEAD CONSTRUCTION Filed Jan. 27, 1958 VENTOR. lg/V158 five/11$ ATTORNEY Patented June 6, 1939 PATENT OFFICE 2,161,133 CYLINDER HEAD CONSTRUCTION James P. Burke, Knoxville, Tenn., assignor of one-half to F. L. McLaughlin, Detroit, Mich.

Application January 27, 1938, Serial No. 187,144

"13 Claims.

This invention relates to. internal combustion engines and has for its object to providean improved cylinder head and piston top construction whichwill give improved engineoperation, the

principles of which are adaptable to engines of the overhead valve or L-head type, or tola combination of both.

The principal object is to provide improved turbulence in the combustion chamber. More specifically it is the object to provide a cylinder head and piston top construction which will set up a high degree of turbulence immediately before firing and which, as the piston approaches its uppermost position, divide the combustion chamber into two compartments in one of which the firing occurs, the other compartment being.

cooperation of formations in the combustionv chamber and on the piston as the piston approaches the upper part, a part of the piston extending into one of said compartments a greater distance than into the other thereof, the compartments being connected in such manner that a high turbulence is caused in the firing compartment at the time of firing, the fired charge thereafter acting as a fuse chamber for igniting the gases in the other compartment and setting up a high turbulence in said other compartment during ignition of the charge therein.

A further object is to provide a two part combustion chamber, one part of which is substantially smaller than the other and serves as a fuse chamber, the charge being ignited to the extent that rapid ignition of the main charge then occurs after passage of the piston over dead center, the fuse chamber being fired well in advance of piston dead center and acting directly on thepiston, thus conserving the main power thrust for the down stroke.

Other objects and advantages will hereinafter become more apparent as reference is had to the accompanying drawing wherein: 45 Fig. 1 is a vertical section through an engine of the overhead valve type, constructed according to my invention,

Fig. 2 is a horizontal section taken along the line 22 of Fig. 1,

Fig. 3 is a vertical section taken along the line 3-3 of Fig. l or on the line 3-3 of Fig. 2,

Fig. 4 is a view similar to Fig. 1 showing my invention applied to a combination overhead an L-head type of engine,

line 5-5 of Fig. 4,

Fig. 6 is a modification of-my invention showing a straight combustion chamber wall and a different piston shape, and

Fig. 5 is a horizontal section taken along th F1Fig. 7 is a perspective view of the piston 01' More particularly i indicates an engine cylinder having a piston 2 therein, the piston having a projection 3, the top of which has an area substantially greater than the remainder 4 thereof. The cylinder head 5 has an intake valve 6 and an outlet valve 1, the valve 6 forming a part of the top of one compartment of a two compartment combustion chamber which is generally of oval shape in bottom plan view, as seen in Fig. 2, the valve 1 forming a part of the top of the other compartment which may be described as generally of crescent shape. The wall 8 which separates the compartments is in the form of a projection from the interior of the cylinder head and is arcuate in bottom plan view. In side elevation it is notched at 9 with the ends of the walls of the notch being curved at ID, the notch extending entirely through the wall 8, horizontally.

When the piston 2 rises on its compression stroke it compresses the fuel charge. The projection 3 rises above the lowermost level of the projection 8 thus dividing the combustion chamber into two compartments. The compartments are in communication by the notch 9 in the projecting wall 8 so that the additional upward travel of the piston into its compartment causes a portion of the fuel charge to be driven from this compartment at high velocity past the step and toward the spark plug ll. Ignition by the spark plug usually takes place before upper dead center of the piston on its compression stroke. In this instance firing occurs when the top of its projection 3 is approximately opposite the lower edge of the projection 8.

As pressure in the firing compartment builds up, the ignited gases will rush into the other compartment tangentially thus setting up a violent turbulence in the compartment comprising. the piston top 3.

In Figs. 4 and 5 a combination overhead and L-head type of engine cylinder is illustrated in which the inlet valve 6a guards the intake passage and the overhead valve la guards the exhaust passage. It will be seen that there is no essential difference in combustion chamber shape nor in piston shape nor in the shape of the projection 8a. Corresponding parts are indicated by the same numerals with the letter a appended. The operation is the same as that described above.

The volume of the firing chamber in which the spark plug islocated is not greater than and preferably substantially less than that of the other compartment, it being intended that the firing chamber serve as a fuse for igniting the greater charge by means of violent flame propagation.

The relative volumes of the two compartments may be varied by shifting the position of the projection 8 or by changing its shape as, for instance, to a straight wall as indicated in Fig. 6.

Figs. 6 and 7 show a modification in which the combustion chamber wall 12 corresponds to the walls 8 and 8a. This wall I2 is of uniform vertical thickness so that, in order to obtain communication between the two compartments of the combustion chamber the top 3b of the piston is cut away at l3. If desired, the bottom of the cutout l3 may be of less height than the vertical wall portion I4 of the piston top 3b so that there is a highly restricted communication between the compartments when the piston is at upper dead center. This will slightly delay the time of ignition of the gases above the top 31) until the piston 2b has proceeded on its down stroke.

What I claim is:

l. A combustion chamber for an engine cylinder having a projection depending thereinto from the top thereof, said projection having a less vertical thickness at one portion than at the re- ,mainder thereof. 1

' 2. A combustion chamber for an engine cylinder having a projection depending from the top thereof and connecting opposite sidewalls thereof, said projection varying in vertical thickness along the length thereof.

3. A combustion chamber for an engine cylinder having a wall depending from the roof thereof and dividing said chamber into two compartments, said wall having a greater depth at one end thereof than at the other.

4. A combustion chamber for an engine cylinder having a wall depending from the roof thereof and dividing said chamber into two compartments, said wall having a step along the length thereof whereby one portion has a greater depth than the remainder thereof.

5. A combustion chamber for an engine cylinder having a wall depending from the roof thereof, and dividing said chamber into two compartments, said wall being curved in bottom plan view and varying in vertical thickness along its length.

6. A combustion chamber for an engine cylinder having a wall depending from the roof thereof, and dividing said chamber into two compartments, said wall being curved in bottom plan view and having a step intermediate its length thereof substantially reducing the height of said wall for a portion of its length.

7. The combination of a cylinder head for an engine having a combustion chamber therein, said combustion chamber having a transverse wall therein separating said chamber into two compartments, a piston reciprocatory toward and away from said combustion chamber, said piston having a projection arising therefrom adapted to extend into one of said compartments, said projection having a cutaway portion whereby said compartments are in communication with each other when said piston projects into its compartment.

8. The combination of a cylinder head for an engine having a combustion chamber therein, said combustion chamber having a transverse wall therein separating said chamber into two compartments, a piston reciprocatory toward and away from said combustion chamber, said piston having a projection arising therefrom adapted to extend into one of said compartments, said wall being partially cut away whereby said compartments are in communication when said piston is in upper dead center position.

9. An engine construction comprising a cylinder having a cylinder head thereon and a piston in said cylinder reciprocatory toward and away from said head, the top of said piston together with the interior of said head defining a combustion chamber, said piston having a projection arising therefrom, the interior of said cylinder head having a projection depending therefrom and with the projection of said cylinder separating said combustion chamber into two compartments, one of said projections being partially cut away whereby said compartments are in communication as said piston approaches its uppermost position.

10. An engine construction comprising a cyl inder having a cylinder head thereon and a piston in said cylinder reciprocatory toward and away from said head, the top of said piston together with the interior of said head defining a combustion chamber, said piston having a projection arising therefrom, the interior of said cylinder head having a projection depending therefrom and with the projection of said cylinder separating said combustion chamber into two compartments, one of said projections being vertically stepped near one end thereof whereby said compartments are in communication near their periphery as the piston approaches its uppermost position.

11. The combination of a cylinder head for an engine having a combustion chamber therein, said combustion chamber having a transverse wall therein separating said chamber into two compartments, a piston reciprocatory toward and away from said combustion chamber, said piston having a projection arising therefrom adapted to extend into one of said compartments, fuel igniting means in the other of said compartments, and means jetting a stream of fuel of restricted cross sectional area directly toward said fuel igniting means.

12. The combination of a cylinder head for an engine having a combustion chamber therein, said combustion chamber having a transverse wall therein separating said chamber into two compartments, a piston reciprocatory toward and away from said combustion chamber, said piston having a projection arising therefrom adapted to extend into one of said compartments, fuel igniting means in the other of said compartments, and means providing a passageway of relatively small cross sectional area between said compartments, said passageway being always open whereby a stream of fuel at high velocity is forced therethrough directly against said ignition means.

13. The combination of a cylinder head for an engine having a combustion chamber therein, said combustion chamber having a transverse wall therein separating said chamber into two compartments, a piston reciprocatory toward and away from said combustion chamber, said piston having a projection arising therefrom adapted to extend into one of said compartments, fuel igniting means in the other of said compartments and a cutaway portion in said projection whereby fuel is jetted directly at said ignition means as said piston approaches its uppermost position.

JAMES P. BURKE. 

